A duty of excise shall be charged on road fuel gas which is sent out from the premises of a person producing or dealing in road fuel gas and on which the duty charged by this section has not been paid.

The like duty of excise shall be charged on the setting aside for use, or on the use, by any person, as fuel in a road vehicle, of road fuel gas on which the duty charged by this section has not been paid.

The rate of the duty under this section shall be £0.3314 a kilogram.

For the purposes of this Act, so far as it relates to the excise duty chargeable under this section, road fuel gas shall be deemed to be used as fuel in a road vehicle if, but only if, it is used as fuel for the engine provided for propelling the vehicle, or for an engine which draws its fuel from the same supply as that engine.

Subsection (2) above shall not apply to road fuel gas delivered to, or in the stock of, the person otherwise chargeable if it was delivered to, or stocked by, him before 3rd July 1972.